2FA vs MFA vs 2SV: Understanding Multi-Factor Authentication

Passwords are no longer enough. Hackers steal billions of them every year. You need a second layer of defense.

The 3 Factors of Authentication

1. Knowledge: Something you know (Password, PIN).
2. Possession: Something you have (Phone, YubiKey, Smart Card).
3. Inherence: Something you are (Fingerprint, FaceID). MFA (Multi-Factor Authentication) means using at least two different types. (Two passwords is NOT 2FA).

The Hierarchy of Safety

1. Passkeys / Hardware Key (YubiKey): The Gold Standard. Cryptographically unphishable. Even if you are on a fake website, the key won't sign the login challenge because the domain is wrong.
2. App Authenticator (TOTP): Google Authenticator, Authy, Microsoft Authenticator. Very secure. Codes change every 30 seconds.
3. SMS / Email: The Weakest Link. Vulnerable to SIM Swapping (hackers convince your carrier to move your number to their phone). Better than nothing, but avoid if possible.

Recommendations: Enable TOTP (App) on every account that supports it. Buy a YubiKey for your Google/Bank/Email admin accounts.

Key Takeaway

MFA is the single most effective security control you can implement. While SMS is better than nothing, hardware keys (YubiKey) are the endgame. Secure your digital life by layering your defenses.